#include <REGX52.H>
#include "Delay.h"
/**
  * @brief 获取独立按键键码 
  * @param  无
  * @retval 按下按键的键码 0~4 无按键返回0
  */
unsigned char Key()
	{
		unsigned char KeyNumber = 0;
		if(P3_1==0){Delay(20);while(P3_1==0);Delay(20);KeyNumber = 1;}
		if(P3_0==0){Delay(20);while(P3_0==0);Delay(20);KeyNumber = 2;}
		if(P3_2==0){Delay(20);while(P3_2==0);Delay(20);KeyNumber = 3;}
		if(P3_3==0){Delay(20);while(P3_3==0);Delay(20);KeyNumber = 4;}
		return KeyNumber;
	
	}